The invention relates generally to improvements in internal combustion engines and, more particularly, to an elongated fuel-air bypass device for use between a fuel-air mixing device and an intake manifold of an internal combustion engine.
Although many improvements have been proposed over the years for the basic internal combustion engine, it has remained the case that the fuel (e.g. gasoline) supplied into the cylinder or cylinders of the internal combustion engine has been a wet saturated fuel. That is, in carburetor engines and throttle body fuel injector engines, liquid fuel is drawn or pumped into an air stream in the throat of the fuel-air mixing device, in order create a fuel-air mixture. This fuel-air mixture is fed directly into the intake manifold and, in turn, into the individual cylinders of the internal combustion engine. In a multi-port fuel injection engine, the liquid fuel is sprayed into the cylinders in an atomized form by the fuel injectors. In any event, the fuel-air mixture entering the cylinders in prior art internal combustion engines has been a mixture of air and wet saturated fuel.
Although the multi-port fuel injection system is an improvement over the carburetor system and has been shown to be approximately 6% more efficient, this increase in efficiency is attained due to a better control of the fuel-to-air ratio. That is, there is no real improvement in the actual combustion of the fuel, but only in the monitoring of the fuel-air ratio under different load conditions, such as during coasting or deceleration.
Wet saturated fuel does not burn. Rather, the wet saturated fuel must be prepared for burning by being vaporized (or gasified). In the prior art internal combustion engines, this vaporization of the fuel has occurred in the cylinder due to the heat of compression and combustion.
Therefore, because the fuel must change state from liquid to gas prior to it being combusted in the cylinder, complete combustion of the fuel is not possible. Therefore, improvements in the efficiency of internal combustion engines to date have been severely limited.
Engine efficiency has also been disadvantageously affected in today's automobiles because of the federal laws preventing the use of leaded gasoline. That is, engines with higher compression ratios will tend to cause preignition or "knocking." This knocking was, however, eliminated by use of tetryl ethyl lead in gasoline (i.e., leaded gasoline). The lead in the gasoline was used to slow the burning of the gasoline and thus slow the movement of the flame front, thereby preventing knocking. When leaded gasolines were outlawed, it became necessary to reduce the compression ratios of new engines in order to prevent the engines from knocking when using the unleaded gasoline. The use of lower compression ratios results in a decreased engine performance and efficiency.
Air pollution due to hydrocarbon and carbon monoxide emissions of internal combustion engines is becoming an increasing concern, especially in metropolitan areas. The major attempts thus far to reduce emissions have been by using lean burn engines and by providing air-cleaning devices, such as the catalytic convertor, downstream of the engine. Although these innovations have proven somewhat successful, the ability to reduce emissions in this manner is limited.
Another problem in prior art internal combustion engines is that of engine flooding, wherein a surplus of liquid fuel becomes present in the engine due to the continual infeed of liquid fuel prior to initial ignition of the fuel.
Various attempts have been made to improve the performance and efficiency of internal combustion engines, but such attempts have been either impractical, or only mildly successful. In U.S. Pat. No. 4,478,198, a fuel treating apparatus is disclosed whereby a dual-compartment insert unit is interposed between the carburetor and the intake manifold of an internal combustion engine, and an elongated conduit is attached between an outlet port of the upstream compartment and an inlet port of the downstream compartment. A heat exchanger and baffle arrangement is provided to heat and cause mixing of the fuel-air mixture traveling through the conduit. However, the fuel treating apparatus of this U.S. patent endeavors only to improve atomization of the fuel-air mixture and, accordingly, the conduit is of a relatively small diameter and cannot accommodate all of the fuel-air flow output from the carburetor. Therefore, a valved bypass opening must be provided between the upstream and downstream compartments to allow for direct fuel-air flow from the carburetor to the intake manifold. This arrangement is thus beset by the same disadvantage as discussed above. In particular, this arrangement continues the prior art concept of feeding a mixture of air and wet saturated fuel into the cylinders of the internal combustion engine. Therefore, it remains necessary for the fuel entering the cylinders to be prepared for burning by being gasified in the cylinders by heat of compression and combustion. In addition, this arrangement is beset by the problem that, if the fuel-air mixture is not allowed to readily flow through the bypass so as to pass directly from the carburetor to the intake manifold, the small diameter of the conduit will effectively starve the engine of the needed fuel-air mixture.
U.S. Pat. No. 4,200,070 is directed to a fuel-air mixture control for supercharged internal combustion engines. In this patent, a supercharger is interposed between an induction conduit leading from the carburetor and an induction conduit leading to the intake manifold. A straight vertical bypass tube bypasses the supercharger so that the fuel-air mixture will pass directly from the carburetor to the intake manifold during idling, and such straight vertical tube is provided directly above a heat transfer plate which is heated by exhaust gases. With this arrangement, any precipitated liquid fuel will drop through the straight vertical tube and onto the heat transfer plate to be vaporized. However, this invention also is beset by the same problem as discussed above. That is, the fuel-air mixture introduced into the intake manifold and the cylinders from the carburetor is a mixture of air and wet saturated fuel. Therefore, as with the other prior art, the liquid fuel must be prepared in the cylinder by being vaporized therein due to heat of compression and combustion, thereby reducing the performance and efficiency of the engine.
Other attempts for improving the performance and/or efficiency of internal combustion engines are disclosed in U.S. Pat. Nos. 5,046,475, 4,355,623, 4,770,151, 4,300,513, 4,286,564, 4,137,875 and 5,040,518. However, these attempts have not presented solutions adequate to overcome the above-described disadvantages of the prior art.